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I am currently in the process of putting an M50 stroker in my 1995 325is.

Got the car last summer. It was auto, black on black, with 173,000km. First thing to happen was an auto to manual swap. I put in some H and R springs and a couple parts that were left over from a previous 1992 325is that was scrapped.

A lot of people are saying / asking why didn't you do an M52 with upgrades. Simply, I just wanted to try something else. I am an automotive engineer with most of my schooling in design, but am currently working at Linamar in quality engineering. So just the idea of something that was more involved and hands on sold me, as I don't get a lot of that at work. I do all my own work, hence making this build a little more worth while.

I will be designing a custom exhaust for it as I have a friend that has the equipment to get it fully bent and created via my drawing as a one piece system. Essentially a piece of up to 9 foot tubing goes in, and your custom exhaust comes out.

I will be doing an almost full rebuild including head bolts, connecting rod bolts, all main and journal bearings, engine mounts, top and bottom end gasket kits, and a port and polish.

I purchased an M54 short block and cam and will be using my existing block. I hope to have this running by the middle of march.

After it is in I will be putting in HSD coilovers, and an E46 M3 6 speed. I will drive the car until mid summer, where the engine will be pulled again and be cryogenically treated. It will be dynoed immediately prior to treatment and then again after to see the gains and improvements. It will also be monitored to see if it runs a little cooler.

After the treatment is done it will see boost and the cryogenics will be put to the test.

Ps wanna get me a job this summer/are you guys hiring? I graduate Mech Eng this spring

Some of the plants are short on man power these days. You shouldn't have a problem getting a job there if you were to put in a resume. But at the same time you shouldn't have a hard time finding a job a little closer to home.

What does cryo treating the block do? I've heard of cryo treated rotors, but this is a lil different

It does the same sort of thing to the block that it does to the rotors. Cryo treating relieves residual stresses left in the components from the manufacturing process and refines the microstructure of the material to give the parts increased durability as well as increased dimensional stability. The increased dimensional stability helps reduce wear on components and increases power transfer characteristics. You might not see any power gains from the cyro treatment itself but the increased durability of the components will give you the ability to run higher compression or higher boost and thatís where the big power gains are going to come from.

It does the same sort of thing to the block that it does to the rotors. Cryo treating relieves residual stresses left in the components from the manufacturing process and refines the microstructure of the material to give the parts increased durability as well as increased dimensional stability. The increased dimensional stability helps reduce wear on components and increases power transfer characteristics. You might not see any power gains from the cyro treatment itself but the increased durability of the components will give you the ability to run higher compression or higher boost and that’s where the big power gains are going to come from.

I see, that's pretty cool. Does it matter how long an engine has been used before it is cryo treated? For example, would it better to cryo treat an engine after it has been run hard for 50K to relieve stresses that happen from (ab)use or right when its new from the factory?

It doesn't really matter no, as the stress in question comes from the machining of the part more so, not the use. But cryo treating an engine that is already worn is only going to help reduce wear from that point on. So as long as the block or part is in good condition, it doesn't really matter when you treat it.

And T.Dot E30 its to have a good control before it is treated. If I don't dyno test it prior to treating it, then I am not going to be able to gauge the effects it has. I need to run it for a while to get good info before it is treated. The whole reason I am treating the engine is because a friend owns a a patent on a cryotreating process but usually does big mining equipment. This is an experiement to see the effects of his process on engines and the gains it has. If I didnt dyno it prior it would defeat the purpose of the treatment.
And the amount of work is the least of my worries. Pulling the engine will be a fun afternoon for me and my buddies, and it will give the me chance to put in a new clutch and the M3 6 speed.